With the S curve, I have all grey scale shades on the LG screen. The lower end of the curve allows the areas of dark contrast to be visible.
The yellow highlights are because the LCD seems to be set for high blue gain. I set the XPS 2's LG screen sitting next to an Apple cinema display (at the Apple store) set for D6500. From the curve above, the red has the highest gain, and the blue is lowered quite a bit.
Here are my settings for the S curve above. To make the curve, go to advanced stetting, and then add 7 points on each curve. It doesn't matter where each point is to begin with. Click on the lowest point and use the arrow buttons to nudge it to match the IN/OUT value. Use the TAB to move to the next point up, or Shift Tab to move down.
R (IN/OUT): 0.00/0.06, 0.03/0.14, 0.10/0.21, 0.51/0.48, 0.91/0.86, 0.96/0.93, 1.00/1.00
G (IN/OUT): 0.00/0.06, 0.03/0.13, 0.11/0.20, 0.50/0.45, 0.90/0.81, 0.97/0.90, 1.00/0.98
B (IN/OUT): 0.00/0.06, 0.06/0.11, 0.15/0.18, 0.58/0.41, 0.86/0.63, 0.93/0.68, 1.00/0.77
I use 4 steps of Vibrance. Move the bar all the way to the left, click on it and then hit the right arrow 4 times.
I use 1 step of sharpening at native resolution, and 2-4 steps at 1400 x 900.
The center dot on each curve will affect the overall contrast, and the easiest way of moving it is nudging it up and down with the arrow keys. Compared to the original setting, this will look much warmer than the original setting. It's still a little cooler than D6500, which is the recommended color temp for monitors. The tool Calibration screen I mentioned above has a really good gray scale, so you can touch up the points to make it as neutral as possible.
I've only tried this on one screen, so these values may need tweaking going from one panel to the next.